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Chd|====================================================================
Chd|  ADIFF2                        source/ale/ale2d/adiff2.F     
Chd|-- called by -----------
Chd|        AETURB                        source/ale/turbulence/aeturb.F
Chd|        AKTURB                        source/ale/turbulence/akturb.F
Chd|        ATHERM                        source/ale/atherm.F           
Chd|-- calls ---------------
Chd|        ALE_CONNECTIVITY_MOD          ../common_source/modules/ale/ale_connectivity_mod.F
Chd|====================================================================
      SUBROUTINE ADIFF2(PHIN,PHI,GRAD,COEF,ALE_CONNECT,VOL)
      USE ALE_CONNECTIVITY_MOD
C-----------------------------------------------
C   I m p l i c i t   T y p e s
C-----------------------------------------------
#include      "implicit_f.inc"
C-----------------------------------------------
C   G l o b a l   P a r a m e t e r s
C-----------------------------------------------
#include      "mvsiz_p.inc"
C-----------------------------------------------
C   D u m m y   A r g u m e n t s
C-----------------------------------------------
      my_real PHIN(*), PHI(*), GRAD(4,*), COEF(*), VOL(*)
      TYPE(t_ale_connectivity), INTENT(IN) :: ALE_CONNECT
C-----------------------------------------------
C   C o m m o n   B l o c k s
C-----------------------------------------------
#include      "com08_c.inc"
#include      "vect01_c.inc"
C-----------------------------------------------
C   L o c a l   V a r i a b l e s
C-----------------------------------------------
      INTEGER I, IE, IV1, IV2, IV3, IV4, IAD2
      my_real DPHI(MVSIZ)
C-----------------------------------------------
C   S o u r c e   L i n e s
C-----------------------------------------------
      DO I=LFT,LLT
        IE =NFT+I
        IAD2 = ALE_CONNECT%ee_connect%iad_connect(IE)
        IV1 = ALE_CONNECT%ee_connect%connected(IAD2 + 1 - 1)
        IV2 = ALE_CONNECT%ee_connect%connected(IAD2 + 2 - 1)
        IV3 = ALE_CONNECT%ee_connect%connected(IAD2 + 3 - 1)
        IV4 = ALE_CONNECT%ee_connect%connected(IAD2 + 4 - 1)
        IF(IV1 <= 0)IV1=IE
        IF(IV2 <= 0)IV2=IE
        IF(IV3 <= 0)IV3=IE
        IF(IV4 <= 0)IV4=IE
        DPHI(I) = (COEF(IE)*COEF(IV1))*(PHI(IV1)-PHI(IE))*GRAD(1,I) / MAX(EM20,(COEF(IE)+COEF(IV1)))
     3 +          (COEF(IE)*COEF(IV2))*(PHI(IV2)-PHI(IE))*GRAD(2,I) / MAX(EM20,(COEF(IE)+COEF(IV2)))
     5 +          (COEF(IE)*COEF(IV3))*(PHI(IV3)-PHI(IE))*GRAD(3,I) / MAX(EM20,(COEF(IE)+COEF(IV3)))
     7 +          (COEF(IE)*COEF(IV4))*(PHI(IV4)-PHI(IE))*GRAD(4,I) / MAX(EM20,(COEF(IE)+COEF(IV4)))
      ENDDO!next I
C-----------------------------------------------------------
      DO I=LFT,LLT
        DPHI(I)=TWO *DPHI(I)*DT1/MAX(VOL(I),EM20)
      ENDDO
C-----------------------------------------------------------
      DO I=LFT,LLT
        PHIN(I)=PHIN(I)+DPHI(I)
      ENDDO
C-----------------------------------------------------------
      RETURN
      END
